fix(react-rules-of-hooks): don't error on hook following non-terminal if statement

[marvinhagemeister]

If an if-statement is placed before a hook it doesn't necessarily mean that the hook was called conditionally. It only is, if the if-statement contains a return statement.

This should error:

function Foo() {
  if (condition) {
    return
  }

  useState(0)
}

...but this is ok:

function Foo() {
  let count = 0;
  if (condition) {
    count++
  }

  useState(0)
}

[dsherret]

LGTM